


13 going on 30

by bibliosexual



Series: Tumblr fic [7]
Category: 13 Going On 30 (2004), Teen Wolf (TV)
Genre: 13 Going on 30 AU, M/M, Writer Stiles
Language: English
Status: Completed
Published: 2016-03-19
Updated: 2016-03-19
Packaged: 2018-05-27 13:26:25
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 5,127
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6286447
Author URL: https://archiveofourown.org/users/bibliosexual/pseuds/bibliosexual
Summary: <blockquote class="userstuff">
              <p>GUYS. I was watching 13 Going on 30 again b/c I’m rom-com trash and I just… I needed a Sterek version. I have no idea if this has been done before, so I just went for it.</p>
            </blockquote>





	13 going on 30

“Do I look cool?” Derek asks, staring at himself in the hall mirror. The leather jacket’s a little big for him — it’s his dad’s — but he thinks it could look okay once he rolls up the sleeves.

Stiles snorts, fiddling with the hem of his baggy plaid overshirt. “You look like one of those drug dealers that hangs out in the park, dude. It’s uncanny.”

Derek gives him the finger.

“Hey, so,” Stiles rummages around in his backpack a minute and comes out with a slender present wrapped in blue tissue paper. “Happy birthday, dude.” 

Derek rips away the wrapping and it’s a comic book, thirty pages, hand-drawn by Stiles himself. 

“Whoa, awesome,” Derek says, flipping it open curiously. “Is this about us? As superheroes?” It looks like Stiles has drawn him as Wolverine, with fangs and bulging biceps, perched on the roof of somebody’s house. 

“Yeah,” Stiles says, grinning, bouncing his weight from his heels to the balls of his feet. “Check it out, I—” and that’s about when the doorbell rings. 

“I’ll look at it later, Kate’s here,” Derek interrupts, pushing past him.

“Oh, uh, okay,” Stiles says, hunching his shoulders. Derek rolls his eyes. Why Stiles expects him to drop everything and read it right this second is beyond him; it’s not like he doesn’t _know_ Derek has a thing for Kate. She’s the hottest girl at their whole school. This is it, his big chance. She can’t see him reading a kids’ book. 

*

After the party, when everyone is gone and Kate’s probably never going to talk to him again and Stiles has shoved him and stormed out because, well, there was a whole mess with a blindfold and Derek thinking he was Kate and nearly kissing him and — well, basically when everything has gone to shit, Derek digs Stiles’ comic book out of the trash where he’d thrown it in a rage and takes it up to his room and broods, flipping through it. 

It takes place at Derek’s 30th birthday party. The villain (their admittedly evil math teacher, Mr. Harris, who Stiles has drawn transforming into a giant lizard) has discovered Stiles’ and Derek’s identities and come after them. There’s an epic battle featuring exploding cakes and laser beams and witty retorts and a secret weapon disguised as a party hat and—  

And it’s actually really good, except that all Derek can think about, a guilty squirm in his chest, is how Stiles must’ve spent hours hunched over his desk in his room drawing it for Derek. Stiles drew Derek as the hero of the story, and Derek feels like dirt.

He falls asleep in the warm light of his desk lamp, with the book still open on his chest.

*

 

Derek wakes in an unfamiliar bed, in an unfamiliar loft apartment that smells like _his_ but also not. It’s spacious and neat, big windows letting in the grey light of early morning, a dull roar of traffic outside, too much traffic to be Beacon Hills.

He wanders into the bathroom and immediately wolfs out, catching a glance of a bulky dark-haired man in the mirror. He blinks a few times and the dark-haired man blinks, too.

It’s like looking at Wolverine-adult-Derek straight from the pages of Stiles’ comic book, or like an older brother he never knew he had: the same hazel eyes and thick eyebrows but newly defined features and stubbled jaw, everything about him sharper and leaner and _adult_. He looks a little disheveled and a lot dumbfounded, standing there in a two-sizes-too-large T-shirt with his mouth hanging open and his arms — his distinctly hairy arms — hanging stupidly at his sides. He has to reach up and prod at his prickly cheek, tentatively, to believe it.

He loses track of time after that, being awed that he’s no longer the skinny weirdo with acne and buck teeth; he’s HOT, with enough muscles to lift his entire couch off the living room floor. He has five different kinds of hair gel in his bathroom and doesn’t know what to do with any of them. He slicks some down over his hair experimentally and it makes him look like a 50s greaser, especially with the leather jacket he finds in his closet. He washes the gel out in the sink.

All of his clothes are scarily organized, socks and underwear neatly folded. There’s next to nothing in his closet except suits and ties, all dark and somber colors and crisp lines. He has to look up on the internet how to tie a tie, and it takes him three tries to get it right. It still looks a little crooked.

He finds out he has a job — at a “consulting firm,” what does that even _mean_? — when he gets a text from a man who’s apparently his driver and who’s waiting outside. Derek gets in the car and goes, because if he stays in that apartment for another minute he’s going to start panicking. It’s bad enough fumbling with his cell phone, which looks like something out of one of Stiles’ sci-fi TV shows.

 

It starts buzzing in his pocket on the drive. He digs it out and finds three incredibly passive aggressive missed texts from someone named ‘Jen’ who calls him 'babe.’ Derek shudders and decides to ignore her.

When he gets into work, he finds out that he’s apparently the boss. No less than six people cower from him as he walks down the hallway, and there’s a huge corner office with his name on the door.

He also discovers that Erica Reyes from high school is his personal assistant. He doesn’t know high school-age Erica that well, really just that she’s quiet and sits with that guy Boyd at lunch. But here, in this future, she grins at him, eyes running appreciatively down his body, and asks him, “What’s with the adorable fluffy hair today? You look like a puppy.”

“I, uh,” Derek says, flushing at the way she’s smirking at him, and ducks into his office.

It’s chaos. His phone keeps pinging with emails and he doesn’t know his computer password and there are too many people with clipboards going by his office wanting him to sign forms and answer questions he has no idea about—

He ends up in the employee lounge with the door barricaded by the couch. He can hear Erica talking about him outside, asking a coworker if he thinks Derek might be sick, he’s acting a little weird today… .

He pulls out his phone — he has one new voicemail from Jen that he ignores — and goes through his contacts frantically looking for Stiles’ number because Stiles is his BFF and because he reads all those sci-fi novels about time travel and parallel universes and stuff, so he’ll know what to do.

Only, he doesn’t have Stiles’ number. He scrolls through the list twice, three times, each time slower, and… nothing. Maybe it’s saved under one of these cryptic names, like “DO NOT CALL”?

It turns out that’s his terribly chatty Great-Aunt Mildred.

Deep breaths, deep breaths.

Derek musters his courage and emerges from the break room and tells Erica to get him Stiles Stilinski’s phone number.

“Stiles, really?” she asks, looking impressed. “I totally had the biggest crush on him in high school. Such a babe.”

 

“Yeah, well,” Derek says gruffly, and he’s blushing again, he can feel it, it’s _awful_ — “Just get me his number.”

“I didn’t know you guys knew each other. Are you going to ask him out?” Erica says with a shit-eating grin. “I bet he’d say yes. He’s always liked guys with lots of muscles—”

“It’s a business call,” Derek interrupts, and closes his office door firmly behind him.

*

 

When Derek calls, Stiles seems surprised to hear from him. His voice sounds different, deeper, and that’s when it hits Derek for the first time that if this is the future, then Stiles is an adult too, whoa.

“Hello? Are you still there?” Stiles asks. “You’re kind of weirding me out right now.”

“Can I come over? Right now?” Derek asks, and there’s a long silence from the other side of the line before Stiles says hesitantly, “Uh… sure? I guess? Do you even know where I live?”

Derek only barely catches himself before he blurts out something stupid like, “Why wouldn’t I?” Of course Stiles wouldn’t still be living in his parents’ house across from the Hales’, he’s an adult, he’s moved out, but… Why wouldn’t his adult self know where Adult Stiles lived? Are they not… friends? anymore?

Derek can’t imagine a world where he’s not friends with Stiles. He feels a little sick.

*

 

It turns out Stiles lives on the other side of the city, above a bicycle store. When Derek knocks on the battered red door, Stiles’ new adult voice yells, “Just a minute!” and there’s a clatter of something dropping on the floor, and then the door is flying open and there’s a man standing there, and Derek feels all the air go out of his lungs.

The last time he saw Stiles, he was thirteen, hyperactive and gangly with braces and floppy hair that fell in his eyes. Now Derek’s eyes zero in on the dusting of stubble on Stiles’ jaw, the more angular lines of his face, the slender musculature of his body and the comfortable way he stands, like he isn’t about to vibrate out of his skin with energy. He’s more contained. He’s wearing a sweater vest and a bowtie. It’s _weird_.

Stiles looks Derek up and down with raised eyebrows, lingeringly. “Uh, hi. You look— wow— never mind.”  He rubs an awkward hand through his hair (his tousled, boy band hair, stylish in a way Derek never would’ve expected) and steps back to let Derek in.

*

 

Since Derek doesn’t really know what’s going on, he just picks a possibility and goes with it, explaining as he paces around the cramped, homey living room of Stiles’ apartment. He’s got amnesia. He has no idea why. He has no idea, in fact, who he is anymore or what he’s doing or anything, really, after his thirteenth birthday.

“What a shitty day to remember,” Stiles butts in. “Of all days.”

Derek winces.

“Never mind,” Stiles says quickly, “it was a long time ago. Stupid middle school stuff. We moved on. What do you want to know?”

“Well.” Derek hadn’t really gotten that far. Mostly it’d just been a mantra of _must see Stiles, must see Stiles_ , a feeling that Stiles would know how to fix this. Fix Derek. Make everything normal and right again. “How about… what do you do? In life?”

Stiles is a writer. A famous sci-fi author who writes best-sellers about werewolf aliens. “It’s not as weird as it sounds,” he says. “Well, okay, it’s pretty weird, but people like it, I like it, so.”

“It sounds amazing,” Derek says sincerely.

“Probably not the kind of stuff you read, though.”

Derek stops pacing. “Are you kidding? You’re the one who got me into sci-fi. You know how much I love it.”

“Oh. You just— I forgot you don’t remember. You kind of got away from all that nerd stuff in high school. I guess it didn’t fit your new ‘cool kid’ persona or whatever.”

“Oh.” That’s… more than a little disappointing.

It’s not all bad. Stiles goes to take a drink, right as Derek makes a joke, and spits water all over the floor and calls Derek an asshole, laughing. He still laughs the same, nose crinkling, his whole body doubling over, mesmerizing. It’s so familiar, the same Stiles under the new look, and Derek feels warm all over.

But the facts of Stiles’ life are all different. It’s a foreign world, an alternate reality where Stiles’ dad is retired, Stiles’ best friend is some guy named Scott, and Stiles keeps beer in his fridge. Beer, but next to no junk food, just the sort of health food crap he used to force-feed his dad. And… Stiles is engaged. To some girl named Heather, his high school sweetheart.

“That’s awesome,” Derek chokes out. He thinks he might be managing a smile. Maybe more of a grimace.

“Yeah,” Stiles says, without much enthusiasm. Or maybe Derek is just biased. “She proposed last summer at the beach.”

“Ah.”

“At sunset. I had sand in some awkward places but it was very romantic anyway. We—”

“Right,” Derek says hastily, “I get the picture.” More than enough of the picture, actually.

“Are you crying right now?” Stiles asks incredulously.

Derek sniffs. “No, it’s just, it’s been a very stressful day for me, okay. The future is stressful.”

Stiles smiles a little, biting his lip. “Uh-huh.”

“Let’s just move on,” Derek decides, because that’s enough bad news for one sitting.

*

 

Derek ends up staying all afternoon, sunk down into Stiles’ red beanbag chair with his knees nearly up to his chin, talking, telling _Back to the Future_ jokes, covering years of history. Most of Derek’s adult life is a large empty landscape as far as Stiles knows because they haven’t even sent each other so much as a Christmas card in over a decade. All Stiles really knows is about high school — that Derek was a star basketball player and one of the most popular guys in school, and that (most shocking of all) he and Kate dated pretty much all of junior and senior year, until they got into some kind of fight at prom and she tried to burn his house down. (“What? Seriously?” Derek says, and won’t believe him until Stiles pulls out the yearbook and shows him the article.)

“And then we graduated,” Stiles says.

“And after that?” Derek asks eagerly, leaning forward.

“I dunno, man,” Stiles says, clearly uncomfortable. “You should probably ask someone else this stuff,” but Derek doesn’t want to. He’s a little afraid that if he leaves, he’s never going to see Stiles again and his whole life is going to be one bleak day after another of the consulting office and strangers and being an adult alone and Jen and his empty apartment with all the hair gel and— Derek doesn’t want to think about any of it.

They talk about the past instead, how they used to spend whole weekends in the arcade or sneak over to each other’s houses after midnight to watch movies with the sound turned down low, or how Stiles used to be the weirdest (and grossest) eater ever, chewing on his straw or cramming a whole fistful of fries in his mouth all at once.

“I still do all of that, actually,” Stiles says, ducking his head. “It’s a wonder I ever got Heather to go out with me. I was sure I’d be ‘never been kissed’ until I was, like, 30.”

Derek snorts. “No way.”

“Yes way,” Stiles protests, cheeks pinking. “I used to have this _huge_ crush on y— on this guy, like, I’m talking bisexual awakening followed by _years_ of pining, and he never even looked twice at me, at least not that way. I’ve never really gotten over it, not fully.”

Derek’s barely started to feel hopeful that maybe Stiles means him — and he didn’t even know Stiles _liked_ guys before today, what the hell — before Stiles is going on, “But I think it was probably a good thing it didn’t work out, you know? Even though I was devastated at the time.”

“Oh,” Derek croaks.

“Yeah, I think it would be too intense, having feelings like that for someone again,” Stiles goes on, looking up at Derek earnestly through his lashes. “It’s too much. Kind of embarrassing, really. I’m glad I don’t get obsessed like that about people anymore, you know?”

“Yeah,” Derek says weakly. “Sure.”

*

 

It’s getting dark when Stiles walks with him the few blocks to Derek’s apartment. Derek was secretly hoping Stiles might invite him to stay, even if he had to sleep on the bean bag, but he wisely decides to keep that news to himself because he knows how creepy it’d sound. Maybe if they were friends, real friends, but. They’re not.

“Nice digs,” Stiles says when Derek lets him in. “Very, um, minimalist.”

“Yeah,” Derek says, looking around at the sleekly uncomfortable furniture, the windows without any curtains, the lack of any spot of color anywhere. Next to Stiles’ apartment, it feels almost sterile, like a robot lives here. The only sign of life is the rumpled bed.

“Well, it’s late. I’m gonna go,” Stiles says at last.

“Okay,” Derek says.

At the door, Derek hesitates and asks, “Would it be weird if I hugged you?”

“Yes,” Stiles says immediately.

Derek’s shoulders slump.

“Okay, okay,” Stiles groans, opening his arms wide. “God, you still do the puppy eyes thing. I can’t—”

So Derek buries his nose in Stiles’ neck and just _breathes_ , all the tension going out of him at the first lungful of Stiles’ warm, slightly cinnamon-y scent. It’s the first thing all day that’s felt even remotely like home, and he closes his eyes and lets himself feel. Stiles’ arms come up to wrap around him hesitantly, and Derek smiles, nosing behind Stiles’ ear, scenting him. “This is perfect,” he whispers into Stiles’ hair.

When he finally pulls back, Stiles half-smiles, bewilderingly _sad_ , and says, “Yeah, I mean, I guess you got everything you ever wanted, huh? You got a hot girl, you got a bunch of cool friends, a great career, and you got rid of the dorky kid who used to follow you around all the time being so annoying, so.”

Derek clenches his fists. “But that’s not what I—” He stops. Where does he even _begin_ with a statement like that?

Stiles shakes his head. “Don’t sweat it. I mean, we’ve both moved on. Right? So. I’ll go.”

Derek closes the door slowly and leans his forehead on the cool metal, watching through the peephole as Stiles walks to the elevator, hands in his pockets. He looks a little lost. Derek _feels_ lost. Stiles is the only thing all day that’s been truly good about his future life, and he’s not even in it, not really.

Derek’s kind of been assuming everything is going to go back to normal after this, like he’ll wake up and be thirteen again and stop feeling this fucking _empty_ , but… but what if this is it, the only life he’s ever going to have? What if it really is some sort of weird amnesia and all of this really happened, just to some other Derek? It makes more sense than thinking this is some kind of magic or a dream, more sense than thinking this is reversible. Fixable.

But if it _is_ fixable…

Stiles is getting on the elevator.

“Wait,” Derek calls, scrambling to open the door, “Stiles,” dashing down the hall, “Wait, wait, stop!”

The elevator doors are closing but Derek just barely slides in.

Stiles looks up, confused, and he’s— he’s got tears in his eyes, what a fucking hypocrite. Derek pushes him back against the wall, hard, and kisses him.

Stiles makes a shocked, sharp little “Mmm?!” in the back of his throat. His head thunks against the wall and he kisses back, pressing up into Derek, furious. His fingers scrabble at Derek’s back, slide up his arms to his shoulders and _grip_ ; Derek can feel his fingernails through his shirt, biting into his skin.

“You—” Stiles starts, and Derek just shakes his head and kisses him harder, opens his mouth just a little and reaches up to cup Stiles’ face in his hands, and Stiles makes a sound that Derek wants to remember forever, high and needy—

Someone clears their throat behind him. Derek freezes. Opens his eyes. The elevator doors are open on the lobby. There are people waiting to get on. People craning to look at them curiously.

“Fuck,” Stiles says, dropping his arms from around Derek’s shoulders. He looks away, then back at Derek’s mouth, dazed. “Fuck.”

He pushes past Derek and out the elevator, and Derek just stands there numbly and lets him go.

*

“Okay, look,” Stiles says, full-on rant mode, as soon as Derek’s rolled groggily out of bed the next morning and found his ringing phone where he’d dropped it on the kitchen floor last night. There had been alcohol. Lots of alcohol. Derek had found a wine rack in Adult Derek’s pantry.

“I think it’s fairly obvious that I, um, that I was talking about you, before, when I was saying that stuff about my first crush” — Derek’s stomach swoops — “but listen, that thing in the elevator? You need to forget that happened. _I_ need to forget that happened. I have a _fiancée_ , Derek.”

Derek doesn’t say anything for a long time, just stares straight ahead at the sleek grey clock on his kitchen wall, the second hand tick-ticking calmly on. Life is fucking surreal.

“I can’t just do that to her,” Stiles goes on. “Or to me. I hadn’t even talked to you in _years_ before yesterday, and the way things ended, before that, it wasn’t good.”

Pause.

“You can’t just ask me to drop everything, my whole life. That’s ridiculous.”

Pause.

“And she’s really great. We have a ton in common and she’s, she’s kind and so beautiful and she works hard, you know? She’s just, she’s so… _nice_.”

Derek swallows against the lump in his throat.

“Would you just say something? Please?” Stiles says finally. “You’re making me nervous. Even more nervous.”

“I understand,” Derek says.

“Great,” Stiles says. He doesn’t sound like he thinks it’s great.

“Do you want to take a walk with me? Today?” Derek blurts, before he can chicken out. “I’m going to call in sick to work, so I don’t have anything going on, and there’s a park near my apartment. We could get ice cream or, I don’t know, kale smoothies or froyo if that’s what you’re into now with the whole health food thing—”

“Derek…” Stiles sounds exasperated.

“Just as friends, two friends hanging out. That’s all. I swear.”

Stiles sighs, a crackle down the line. “Just friends. Okay.”

*

So they spend the afternoon together. They get a sugar high at an ice cream shop, Stiles dripping ice cream all down his shirt when he gets too distracted talking, and when that’s done they hunt down the arcade where they used to go as kids and wander around downtown in the last of the evening light, looking in shop windows and sneaking glances at each other, Stiles scuffing his sneakers on the sidewalk and turning away when he catches Derek at it.

It’s kind of like how it used to be between them, easy conversation and playful teasing and Derek’s ribs aching from laughing, but now there’s this tension, too, drawing him closer. He wants to touch him, his hand or his arm or his neck or — anywhere. Even just the slightest brush of fingers. But — just friends. Right.

It’s so _hard_ , though. They walk a few more blocks and Stiles spots a dog, crouches down to pet it, snorting when it licks his nose, and looks up at Derek with delight, and Derek aches. When Stiles stands back up, beaming, his hair a little messy in the wind, Derek just sways into his space, breathing in the same air, listening to Stiles’ sharp inhale. The backs of their hands brush. Everything between them hangs perfectly still, Stiles’ eyes flicking up to meet Derek’s, the smile slowly fading to something more serious—

Of course that’s when Stiles’ phone rings.

 _Heather_.

Stiles presses the phone to his ear and turns away from Derek, shoulders stiff, and says things like “Yeah, babe, sure,” and “Love you,” while Derek stands there, fiddling with the hem of his shirt and trying not to listen.

“I have to go,” Stiles tells Derek, flatly, when he hangs up. He keeps his hands carefully at his sides. “Wedding stuff, you know.”

“Yeah,” Derek says.

Stiles nods awkwardly, averting his eyes. “It’s probably actually going to keep me pretty busy for the next few weeks, so, um, this might be the last time we—”

“I love you,” Derek blurts, and Stiles’ eyes snap to his. “You’re still my best friend, Stiles. More than that.”

Stiles gapes at him, and then starts pacing, tugging on the wild strands of his hair. “Damn it, you can’t just _say_ that,” he says. “I was handling it, okay, I was doing so _well_ , I was over it. Why did you have to go and make everything so difficult again?”

“It doesn’t have to be,” Derek says, stupidly.

“Look.” Stiles sighs. “The way I feel about you—it’s not enough, Derek. Since you came back, I’ve just been indulging a dream life I never got to have. I’m not ever going to have it now. That’s just how it’s got to be.”

“Why?” Derek demands, catching Stiles’ hand before he can turn away. “Why can’t we just have this?”

“Because we were best friends, Derek,” Stiles snaps, “and I spent three weeks making you a comic book for your thirteenth birthday, and at your party you threw it away and shoved me into a wall and told me you hated me, and then you never talked to me again until a day ago, that’s why. You’re a dick.” He jerks his hand out of Derek’s. “You got your chance and you blew it.”

“I’m sorry,” Derek says, helplessly.

Stiles looks at him, then, really looks at him, and all the fight seems to go out of him. “I know,” he says. He’s almost tender when he touches Derek’s cheek and tells him goodbye.

*

Derek thinks about his apartment, all that empty space, and wanders off down the street instead, lost, hunching into himself against the early night chill. Maybe he’ll just keep walking like this. Forever.

On impulse, he hails a taxi and uses the credit card in his wallet to pay for the trip from San Francisco to Beacon Hills. It takes about an hour and a half, he’s not sure; he zones out the whole way, gazing out the window.

His parents still live in the comfortable split-level house at the end of the street, across from the Stilinskis. The spare key’s still under his mom’s blue flower pot on the back porch.

His parents and his sisters aren’t home; the house is dead silent.

His bedroom’s been turned into a home office for his dad, painted neutral beige and smelling like dust. There’s almost nothing of his sitting out, and not even the most faded scent of him lingering anywhere. It’s like he hasn’t been here in ages.

His old bookshelf is still in the corner, though. They didn’t get rid of that.

Derek runs a hand over the rows of paperbacks, their spines bent from rereading, and his fingers catch on something more slender tucked between a couple Stephen King books. He pulls it out and suddenly he’s blinking back tears, sinking down on wobbly legs to sit at the desk, because it’s Stiles’ comic book.

The pages are yellowing now at the corners, the cover torn a little on one edge. It’s really the last artifact, he thinks, of the days when things were still great with Stiles and he hadn’t started ruining his life. The last token of friendship he ever got from Stiles. The last one he ever will get, now.

*

When Derek wakes up, it’s still night, and he has a crick in his neck from falling asleep in his dad’s office chair. Only — he’s not in the office chair anymore, he’s in a bed, and the room doesn’t smell like dust and fresh paint. It smells warm and lived in and a little like musty sheets because his mom is making him do his own laundry now, which means it just doesn’t get done _period_ , and—

He reaches up, tentatively, and touches his cheek. Peach-soft, not even a hint of stubble.

Holy shit.

He scrambles out of bed, the covers tangling around his knees, and nearly headbutts his dresser drawers in his haste to get to his feet and look in the mirror.

When he does, he can’t help it: he starts laughing, a little uncontrollably. He’s not even sure why. It’s not funny. It’s so far from funny. It’s the most relieved he’s ever felt about anything. It just feels so _good_ to have acne and an awkward haircut and skinny arms again.

Through the thin walls that separate his room from Laura’s, he can hear her blasting “Smells Like Teen Spirit,” which means she’s probably on the phone with her boyfriend and doesn’t want anyone with werewolf ears listening in. Derek grins and races into her room. “What’s today?” he demands, grabbing her by the shoulders.

She glares at him, cradling the phone against her chest. “Your birthday, _duh_ , let go,” she snaps. “I’m kind of in the middle of something here, _god_. You get more obnoxious every day.”

“My _thirteenth_ birthday, specifically,” Derek says. “Right?”

Laura rolls her eyes. “Yes, dumbass—”

Derek’s hugging her and racing out the door before she even has time to be confused.

Across the street, the light is still on in Stiles’ window.

When Derek climbs up the porch rail and onto the roof outside Stiles’ window, Stiles is lying on his bed, wide awake. He’s a scrawny kid again, floppy-haired, wearing about three layers of shirts and staring up at the ceiling with his walkman on. He jolts to his feet with a bitten-off yell when Derek clambers through his window to land clumsily on the floor.

“I—” Stiles starts, yanking off his headphones, “you—”

“I’m sorry,” Derek says, breathless. “I loved your comic book. It’s the best thing I’ve ever seen. You’re amazing.”

“Yeah, well, you’re a dick,” Stiles says, flushing.

“I know,” Derek says. “I’m going to make it up to you, though.”

Stiles swallows, eyes wide. “You’re gonna be buying me milkshakes for, like, a _year_ for this.”

“Done,” Derek says. “All the milkshakes you want. It could even be, like, a date. If you wanted.”

Stiles gapes at him.

Derek risks a smile and steps in a little closer, into Stiles’ space. “Tell me if you want me to stop.”

“Stop, uh, stop what?” Stiles whispers, eyes like saucers and fixed on Derek’s mouth.

Derek grins, cups Stiles’ jaw and kisses him. Stiles makes the _best_ noise, hands flailing and finally settling on Derek’s waist, and kisses back.

*

A half hour later, Derek gets kicked out of the Stilinski house when the Sheriff hears them from down the hall. It’s totally worth it.

*

At 30 years old, Stiles and Derek live together over the bicycle shop.

**Author's Note:**

> Also on my [tumblr](http://bibliosexxual.tumblr.com/post/141274121616/13-going-on-30-au)~


End file.
